Malicious PDF — malware analysis report

Static analysis result for SHA-256 9f959f3e6bb129d4…

MALICIOUS

PDF

79.8 KB Created: 2021-09-10 17:45:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: a36ca28796a062b076973bc145e9121b SHA-1: b43fda480d30937c800dff83e25ba35bd79ea6f6 SHA-256: 9f959f3e6bb129d4ede6548a497a33cc184094ed1e2d0a3f179d1d5a4478bf3f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users to malicious content. The presence of these links and the overall structure strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://by-express.com/upfiles/editor/files/kutekimafipemukuju.pdf In PDF document text
    • http://01host.ru/userfiles/files/ranebojugajapesizuseg.pdfIn PDF document text
    • http://askaudit.ru/price/kizisozosatikek.pdfIn PDF document text
    • https://maxlinder.com/admin/assets/ckfinder/userfiles/files/wunabar.pdfIn PDF document text
    • https://aarhuskortet.dk/images/file/20017529045.pdfIn PDF document text
    • https://lensprovn.com/ckfinder/userfiles/files/26957399260.pdfIn PDF document text
    • http://gamebonda.com/ckupload/files/53658182561.pdfIn PDF document text
    • http://universalthailand.com/images/uploads/ckfinder/files/96706224735.pdfIn PDF document text
    • http://www.its-dph.cz/admin/fckeditor/editor/userfiles/file/98638600845.pdfIn PDF document text
    • https://totalsewa.com/userfiles/file/rovegubimilugogezumeloram.pdfIn PDF document text
    • http://puebloexec.com/userfiles/file/xekufakawavewa.pdfIn PDF document text
    • https://smartcrm.cloud/upload/files/feputol.pdfIn PDF document text
    • https://permargi.com/files/galeria/files/51584070982.pdfIn PDF document text
    • https://cosmopolitanhotel.lastrada.bg/uploads/wysiwyg/files/82831950875.pdfIn PDF document text
    • https://brukspec.pl/upload/file/rudupuwolibojo.pdfIn PDF document text
    • https://www.getfitcrew.com/wp-content/plugins/formcraft/file-upload/server/content/files/161305f59cd820---43050836237.pdfIn PDF document text
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/16132a7fbc0981---96439105199.pdfIn PDF document text
    • https://nordavril.com/userfiles/file/fezotubasobojivajikaxaw.pdfIn PDF document text
    • https://grootformaatspandoeken.nl/userfiles/file/xegun.pdfIn PDF document text
    • https://anbc31.iscriptscloud.com/app/webroot/files/file/83082751964.pdfIn PDF document text
    • https://satuldelut.ro/ckfinder/userfiles/files/79089450056.pdfIn PDF document text
    • https://bokseinstituttet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16131121c4bf26---javepamor.pdfIn PDF document text
    • https://themodernla.com/wp-content/plugins/super-forms/uploads/php/files/d9ec2c9897a154016bd3f95ea8e25d05/74791109193.pdfIn PDF document text
    • https://iringmalaysia.com/ckfinder/userfiles/files/70721936873.pdfIn PDF document text
    • http://yogathoitrang.com/quangbasanpham/app/webroot/upload/image/files/xadudirojovez.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=my+little+pony+apk+downloadPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d34e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD34E 10400 bytes
SHA-256: 78eb6f64e2d1e4fcad2918e607179535a12af27bab551e274d166d5f505b7c7f
font_01_sfnt_off0000eaf9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAF9 17988 bytes
SHA-256: 94e0639d920896538522892132c6b379df14fb5c01f6e2cd1bfadcbdca9852a5
font_02_sfnt_off0001198a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1198A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1